Two manufacturers are to submit a joint bid to build HS2 trains in Britain.
Bombardier Transportation and Hitachi Rail announced that they will form a joint venture to compete for the £2.75 billion contract to design, build and maintain at least 54 new high-speed trains.
Manufacturing would be expected to be split between Bombardier's plant in Derby and Hitachi's factory in Newton Aycliffe, County Durham.
The firms, which also have maintenance facilities across Britain, employ more than 5,000 people in the country.
They had previously submitted separate bids for the contract.
Bombardier and Hitachi described themselves as a "tried and tested high-speed team", having already built a high-speed train for Italy.
The latter built the original Shinkansen bullet train in Japan in 1964 and continues to develop updated versions.
Hitachi managing director Karen Boswell said the firms will "draw on a huge wealth of UK experience".
She added: "Our aim is to deliver a new British icon that will be recognised around the world - a Spitfire for the British railway."
Her UK counterpart at Bombardier, Richard Hunter, said: "We will combine both companies' global high-speed expertise with unrivalled British experience, and help generate skills and prosperity across a number of UK regions."
The formal tendering process is due to start later this year, with the winner announced in late 2019.
The trains will be used for phase 1 of the £55.7 billion high-speed railway, which will link London and Birmingham from December 2026.
They will also serve destinations on conventional lines beyond the core HS2 network, including York, Newcastle, Liverpool, Glasgow and Edinburgh.
Four other bidders have also been shortlisted - Alstom Transport, Patentes Talgo, Siemens and CAF.
The latter's bid failed to make the shortlist announced in November last year, but an HS2 Ltd spokesman said it has been added "to ensure a robust competition" following the decision by Bombardier and Hitachi to form a partnership.
The award of UK train-building contracts to foreign firms with overseas manufacturing plants has been criticised in recent years.
In 2011, Germany-based Siemens was handed a £1.6 billion deal to build trains for London's Thameslink, and in 2016 Spanish company CAF won a £490 million contract to manufacture trains for Arriva Rail North.
Alstom opened a train technology and manufacturing facility in Widnes, Cheshire, in June last year, while CAF will open a train factory in Newport, Wales, this autumn.
Another Spanish manufacturer, Talgo, is planning to build a factory in the UK and has visited potential locations in Leeds and Liverpool.